For Extra-Fine carving and lettering details. These tools are used for wood, plastic, aluminum and solid surface materials. Maximum RPM 28, 000., #45620, Angle (a°) 30°, cutting height (B) 0.413", shank (D) 1/4, overall length (L) 2, tip width (T) 0.0108", 45620 Solid Carbide 30 degree engraving 0.0108 tip width x 1/4 inch shank signmaking